Self computing leveling rod



June 30, 1931. c. H. MILLS SELF COMPUTING LEVELING ROD INVENTOR. GhESTifiW/LLfi Byw ATTORNEY. v

Filed April 2. 1928 Patented June 30, 1931 UNITED STATES CHESTER H.MILLS, F WICHITA, KANSAS SELF (JOTMIEU'IJING- LEVELING- ROI) 3Application filed April 2, 1928. Serial No. 266,507.

The invention relates to improvements in leveling rods used by surveyorsand others, in which sliding elements are used to brin to view correctnumerals as indicated by the line of sight of the levelmans instrument.Among the principal objects of the invention are; first, to provide ameans of obtaining elevations by simply reading the figures interceptingthe said line of sight: second,

1 by means of specially devised locking elements; to prevent the movableparts of the rod from slipping while in use: third, to permit the use ofa long rod, an intermediate rod, or a short self-computing rod as may bedesired. By means of my invention a great saving of time is effected;also it greatly simplifies the matter of computations. My improved rodis much more easily handled I than the computing rod generally employedand accuracy readings is assured. These and other advantages will beapparent from the description of the drawings and as specificallypointed out in the claims.

In the drawings; Fig. 1 represents a front view of my improvedself-computing leveling rod, with parts broken away to enable the rod tobe brought within the confines of the sheet. Fig. 2 is a rear view ofFig. 1. Fig. 3 is a side view of Fig. 1. Fig. 4 represents an enlargedside view of the base element seen in Fig. '2 with parts removed todisclose operative details. Fig. 5 is a side view of Fig. 4 omitting thescrew element for convenience of illustration but showing base 13 not onFig. 4. Fig. 6 represents a detail showing the upper rod release seen inFig. 2 while Fig. 7 shows a side view of the same with parts removedfrom the view seen in Fig. 3. Fig. 8 represents a sectional view takenalong the line VIIIVIII in Fig. 2 looking in the direction of thearrows; Fig. 8?) represents a sectional view taken along the line bb inFig. 2 looking in the direction of the arrows; while, 80 represents asectional view taken along the line 00 in Fig. 2 looking in thedirection of the arrows. Fig. 9 is a detailed side view of the means foradjusting the front foot numeral plate as seen in Figs. 1,

i 2 and "3. Fig. 10 is a front'view of Fig. 9

and showing the hook assembly on the bottom of the foot numeral plateofthe upper rod. Fig. 11 represents a fragmentary portion of a footnumeral plate and its cover ing strip with openings therein throughwhich desired numerals may appear in selected order. Fig. 12 shows frontand side views of the automatic catch for the target. Fig. 13 showsfront and side views of the automatic plate, catch seen in Figs. 2 and8?). Similar numerals of reference indicate corresponding partsthroughout all the figures of the drawings.

Referring to the drawings; 10 represents the lower rod element while 11represents the upper rod portion. Below the lower rod at 13 is seen thebase member slidably positioned intermediate the paired U-shaped guides14 and .15 attached to the rod 10. At 16 in Figs. 2 and 4 is a plateprovided with a threaded boss 17 receiving the screw 18 rotated by thethumb nut 19 housed in bearings in the U-shaped bracket 20 which isattached by screws 21, 21 to the rod 10. Also the plate 16 is slottednear its ends as at 22 and 23 to pass screws 24 and 25 entered into therod 10'as seen in Fig. 4,.the slots 22 and 23 permitting the plate 16 tohave vertical movementsunder adjusting conditions as required andcarried out by the manipulation of the thumb nut 19 to move the boss 17.It will be noted in Fig. 5 that at spaced positions upon the face of theplate 16 are square cut grooves such as 26 adapted to receive the foot27 of the plunger 28. A U-shaped plate 29 in Fig. 2 is attached byscrews 30 (Fig. 2) to the base member 13 and is slotted at 31 to passthe head 28 of the plunger. At 32 Fig. 5 is a spring on the stem of theplunger 28 hearing between the enlarged portion 33, and the plate 29normally forcing the foot 27 to engage a selected groove 26 which wouldlock the base element 13 in a fixed position relative to the rod 10. Tobreak this locked connection the plunger 28 is drawn outwardly thengiven a quarter turn as in Fig. 2 or so that the head 28 standstransverse to the slotv 31 and bears against the plate 29. This holdsthe foot 27 out of engagement with a groove 26 to permit adjustments aslater disclosed.

One of the main objects of the invention is to permit the locking of theupper rod at various foot elevations or so as to permit the rodman toemploy a rod no longer than is necessary, and to provide a means forchanging foot numerals.

At spaced intervals of a foot each upon the rear face of the rod 10 asseen in Fig. 2 are attached by screws, metallic sockets such as 33. Uponthe base of the rod 11 is a base plate 34 (see Figs. 6 and 7) slotted at35 to pass the disc 36, which is slidably mounted adjacent the head 37of the plunger 38. In Fig. 6 the disc 36 has been slid upwardly toengage against the shoulder 351 to permit engagement of plunger 42 withsocket 33 in Fig. 7 for locked position of extended rod. The plunger 381s horizontally operative in an opening through the base ofthe member 11and in which a lever 39 pivoted upon a fixed pin 40 and hinged at 41 tothe plunger 38 actuates the plunger 42 against the spring pressure 43 todisengage said plunger 42 from the socket 33, or to permit the reversemovement as explained above. Pushing in and down upon the disc 36 breaksthe plunger look as in Fig. 7, the disc 35 looking behind the plate 34as shown by dotted position 3522 Thus it will be seen that the upper rodcan be quickly raised or lowered as may be desired so that no longer rodis used than is essential. This is of material advantagein levelingthrough trees and other close quarters.

At 44 is the usual target. t its topmost position it is positivelypositioned by means of the automatic catch seen in Figs. 3 and 12. Aspring-actuated plunger 45 detachably engages the socket 46 for suchpurpose.

Upon the face of the rod 10 Fig. 1 is a foot numeral plate or strip 47seen in Fig. 11. This strip may be shifted up or down upon the face ofthe rod 10 a short distance. The strip 47 is covered by a metallic stripor plate 48 which is graduated with spaced numerals 1 to 9 inclusive oras otherwise de termined. The plate 48 is aiiixed to the rod 10 and isperforated to provide a square slot through which numerals on the shiftstrip 47 desi nating foot marks may appear, they being shown upon thestrip 47 as in Figs. 1 and 11. These numerals are so spaced as will beobserved so that if for instance the numeral seven appears in the slot50 as in Fig. 11, then the numeral eight will appear in the next lowerslot 50, numeral nine in the slot 50 below that etc., while numeral sixwould appear as in Fig. 1 .in the slot above the numeralseven seen inits slot in Fig. 11. The strip 47 is shifted .in either direction lessthan a foot orthe distance necessary to expose ten numerals of aconvenient size to be seen through a slot 50 in the plate 48 as laterexplained. The purpose of this arrangement is such that if the end 49 ofthe base member 13 be rested upon a bench mark, its known elevation isadj ustably transposed upon the rod or so that once this has beenestablished all further elevations may be read direct from the rodwithout further calculations. Assuming for instance an elevation of thebench mark of 106.1. The strip 47 would be shifted by means laterdescribed until numeral 6 appears in the opening or slot 50in the plate48 closest to the line of sight. This would not necessarily bring theproper decimal in this case .1 exactly into the line of sight. Themember 28 would be pulled out to break connection of the element 27 withthe groove 26 it might be in, then the plate 16 would be again engagedby such element 27 within a more proper groove 26 closest to the line ofsight, thence by adjusting the screw 18 the plate 16 would be finallyshifted in its guides 22 and 23 to the exact point so that the line ofsight would read for instance the 6.1 portion of the bench mark reading106.1 above mentioned for purposes of illustration. Readings applianceto the lower rod at any other points at which elevations were desiredwould be read direct from such rod, for wherever the line of sight wouldintersect such lower rod the proper foot numeral be it 6, 7, 8 and 9would show through its proper slot 50 and the remainder of the elevation would be read from the strip 48. It .100

will thus be seen that the slots 50 are maintained in a fixed positionupon the rod 10 and thestrip .47 merely slides upor down a foot or lessdistance behind the plate 48 so that the proper numerals register in se-V ries through said slots 50 for the purposes designated. The shiftingof the plate 47 above referred to is accomplished 'by the meansillustrated in Figsa3, 9 and 10. ,A slot 51 as in Fig. 8 is made throughthe side of the upper end of the rod 10. A plate 52 of L-shape slidablyarranged therein .is screwedtoa second L-shaped plate 53 (Fig. 8) whichin turn is riveted to the plate 47.

At 54 (Fig. 3) is a slotted strip having ten transverse slots such as 55intersecting the long slot 56 of the strip 54. A slidable element 57having a handle element 58 has a pair ofslots receiving the pins 59 onthe plate 52 or so that the handle 58 may be pulled out to disengage itsbase from any cross slot 55 and permit the handle to move verticallyinto a new position to register with any other selected slot 55 thusmoving the strip 47 to bring the proper numeral such as the six abovereferred to, near the line of sight andto set the other numeralsin theirproper windows for rod reading purposes. The spring 60 (Fig. engages anotch in the plate 52 to hold the part 57 against movement.

A plate similar to 47 appears upon both faces of the upper rod 11 andeach face has a covering plate similar to the plate 48. The plates 47mand 47g Figs. 2 and 8c are connected through a slot in the upper end ofrod 11 by a cross tie 61 riveted to each. The composite plates 47ae47gare adjusted by means of a projection 62 on plate 47% which is slidablyarranged in the guide 63. The slots in which the members 52, 53 and 61slide are of the correct length to allow all foot numerals O to 9 to beshown in their desired openings in the plates 48, 4850 and 48; Theseplates are rigidly attached by screws flush with the surface of the rods10 and 11.

Pushing up or down upon the member 62 moves the plates 47w-et7y to anydesired locked position as illustrated in Figs. 8b and 13. This causesfoot numerals on the plates 47a; and 473 to appear in the proper slot 50of the upper rod 11. Holes such as 64 are drilled in the plate 47% atspaced intervals, corresponding to the spacing of the slots 55, toreceive the spring actuated plunger means 65 to hold the proper footnumerals in their respective slots 50 as above. The plunger 65automatically looks or detaches as will be readily understood.

Fig. 10, which is a detail of the dotted portion at 53, Fig. 3 alsoincludes at the upper left hand corner thereof a small plan view of thestrip 479 and hook 66 riveted to the base thereof. The plate 47 onmember 10 being held in its proper position by the plunger 58, the upperrod, if raised to its full length, causes the hook 66 to engage the hook67 on the member 53; the plunger 65 releases and the rod 11 extends toits full length, the hook engagement 6667 holding then the plates 47%and 47y in proper position to conform to the lower plate 47 or so thatthe proper foot numerals on the extended rod 11 will then appear throughtheir slots 50 and check with the foot numerals upon the lower rod 10and in proper spaced order. This then gives the correct reading for theentire length of the rod 1011. The hook 66 slides in the groove 68 inFig. 2. The rod is raised to its full length, the member 34 strikingagainst the metallic stop 69 in Figs. 1 and 2. WVhen the rod is fullyclosed it rests against the metal stop 70, Figs. 1, 2 and 3. If targetis to be read, then the elevation is read by the rodman on the back ofthe upper rod 11.

My rod is more accurate than other rods since the part 17, 19 and 20give a fixed adjustment. Where rollers are used exact readings areimpossible, owing to the fact that they are liable to wear, and ribbonsor ribbon rods are liable to slip upon rollers and are also subject tovariation caused by expansion and contraction of the ribbon.

- Exact readings are possible with my rod due I tothe fact that they aretaken on the'fixed wood part of the rod.

Such modifications may be employed as lie within the scope of theappended claims.

Having fully described my invention, what I now claim as new and desireto secure by Letters Patent is; j

1. In a device of the class described, a lower rod and an upper rodslidably associated; an extension below the lower rod as a base elementand means for adjustably positioning the same with respect to said lowerrod; said means including a plate slidably mounted on the lower rod nearthe base thereof, said plate having openings for receiving a plungermechanism; a plunger mechanism carried by the extension member andadapted to engage within a selected opening in said plate for adjustablypositioning the parts as previously stated.

2. In a device of the class described, a lower rod having a plateslidably mounted thereon near the base thereof, an extended foot portionand a plunger mechanism associated therewith; said plate having openingsfor receiving said plunger mechanism, said plunger means beingpositioned within said extended portion at the base of the lower" rodand to enable varied positions of the rod and extended portion to bemaintained as desired.

3. In a device of the class described, an upper rod having strips onopposite faces, each having openings therein; a pair of sliding stripsconnected at their top ends through a slot in said rod, said stripsbeing arranged to move behind the face strips with which they areallied, each strip bearlng numerals in series readable through sa1dopenings in proper series relationship; and means for securing saidstrips in adj usted position at selected intervals; one of said stripscarrying a hooked end; a lower rod slidably connected to the upper rod,a face strip thereon, a sliding strip carrying foot numerals arrangedbehind the face strip with openings therein to permit viewing of properfoot numerals in series; means for adjustably setting said strips toexpose said foot numerals at proper slotted openings and a hook assemblyon said setting means for engaging the hook on the strip of the upperrod to properly associate the lower numeral strip with the upper numeralstrips under extended rod conditions to present a proper spacing of footnumerals at slotted places of the upper and lower rods for readingpurposes.

4. In ardevice of the kind described, an upper rod having strips onopposite faces affixed to the rod, each strip having openings at spacedintervals; a pair of sliding strips connected at their top ends througha slot in said rod, said strips being movable behind said face strip ashort distance in either direction and numerals in series marked on saidstrips and readable through said openings in a proper seriesrelationship.

In testimony whereof I aifix my signature.

CHESTER H. MILLS.

